Enterprise storage is computer storage designed for large-scale, high-technology environments. When compared to commercial/consumer storage, it has higher scalability, higher reliability, better fault tolerance, and much higher initial price compared to commercial/consumer storage. Enterprise storage involves the use of a storage area network (SAN), rather than a distributed storage system, and includes benefits such as high availability and disaster recovery, data sharing, and efficient, reliable backup and restoration functions, as well as centralized administration and remote support. Commercial/consumer storage systems are those that are used by consumers or for general commercial use. In general, the requirements of an enterprise storage system, and differences from a consumer type system, can be expressed with respect to four attributes: Performance, Reliability, Durability, and Workload. These four parameters are used to measure the reliability of data storage with respect to workload.
In general, the performance standard for an enterprise storage system needs to be the “best in class” under a given workload. Conversely, a consumer or commercial performance needs only be “good enough” for a particular application. Generally, enterprise storage systems need to maintain a low failure rate, typically under 3%. In comparison, the failure rate for commercial or consumer memory is rarely tracked. With respect to durability, the enterprise system needs to withstand about 5 years of use where a commercial system can be expected to endure 3 years of use. Further, during those working conditions, the enterprise system must be available for 24 hours a day for seven days a week where a commercial system need only be available for 8 hours a day for 5 days a week.
In an effort to increase performance, both enterprise and commercial storage systems have begun to move to a non-volatile memory type called flash memory which can provide higher reliability, lower power consumption and quicker access times than traditional magnetic disk-based storage. The quicker access time, higher reliability, and lower power consumption of flash memory comes at a cost of a limited number of possible writes to the flash memory and hence a limited lifetime, particularly when compared to disk drives.